Measurement of the Inclusive Energy Spectrum in the Very Forward Direction√ in Proton-Proton Collisions at S = 13 Tev

EUROPEAN ORGANIZATION FOR NUCLEAR RESEARCH (CERN)

CERN-EP-2016-313 2017/08/16

CMS-FSQ-16-002

Measurement of the inclusive energy spectrum in the very forward direction√ in proton-proton collisions at s = 13 TeV

The CMS Collaboration∗

Abstract

The differential cross section for inclusive particle production as a function of energy in proton-proton collisions at a center-of-mass energy of 13 TeV is measured in the very forward region of the CMS detector. The measurement is based on data collected with the CMS apparatus at the LHC, and corresponds to an integrated luminosity of 0.34 µb−1. The energy is measured in the CASTOR calorimeter, which covers the pseudorapidity region −6.6 < η < −5.2. The results are given as a function of the total energy deposited in CASTOR, as well as of its electromagnetic and hadronic components. The spectra are sensitive to the modeling of multiparton interactions in pp collisions, and provide new constraints for hadronic interaction models used in collider and in high energy cosmic ray physics.

Published in the Journal of High Energy Physics as doi:10.1007/JHEP08(2017)046. arXiv:1701.08695v2 [hep-ex] 15 Aug 2017

c 2017 CERN for the beneﬁt of the CMS Collaboration. CC-BY-3.0 license

∗See Appendix A for the list of collaboration members

1 Introduction Particle production at very forward rapidities (|η| > 5) in high energy hadronic collisions re- ceives contributions from multiparton interactions (MPI), initial- and ﬁnal-state radiation (from the hardest parton scattering), fragmentation of the so-called “beam remnants”, plus diffraction [1]. The sum of all these particle production mechanisms, typically referred to as the “underlying event” [2], is modeled phenomenologically in hadronic Monte Carlo event generators with parameters tuned from the data [3–5]. A good understanding of forward particle production is important for a complete description of the ﬁnal states in proton-proton (pp) interactions at colliders, as well as to accurately simulate extensive air showers induced in the earth atmo- sphere by very high energy cosmic rays [6]. In particular, forward charged hadron production has direct impact on the total number of air-shower muons at the ground, whose measurement shows unexplained excesses compared to model predictions [7]. The rapidities covered in the presented measurement (−6.6 < η < −5.2, still well separated from the beam rapidity y ≈ 9.5) are mostly sensitive to the MPI activity [8]. Previous studies of very forward particle production in pp collisions have been carried out at center-of-mass energies of 0.9, 2.76, 7 and 8 TeV by CMS [8, 9], at 7 and 8 TeV by TOTEM [9–11], and at 7 TeV by LHCf [12, 13]. The present paper reports new measurements of inclusive energy spectra at a center-of-mass energy of 13 TeV. The data are discussed in terms of the production of electrons and photons (mostly from π0 decays), as well as hadrons (mostly π±) in the very forward direction covered by the CASTOR calorimeter of the CMS experiment at the CERN LHC. CASTOR [14] covers the pseudorapidity region −6.6 < η < −5.2, and can distinguish between electromagnetic and hadronic energy depositions. CASTOR is only installed on the negative z-side of CMS, and hence has acceptance at negative pseudorapidities. Because of CASTOR’s very forward location, the data are sensitive to parton interactions at very small and large fractional momenta in the proton, x < 10−4 and x → 1.

2 Experimental setup and Monte Carlo simulation The central feature of the CMS apparatus is a superconducting solenoid of 6 m internal diame- ter, providing a magnetic field of 3.8 T [15]. Within the field volume in the central region are a silicon pixel and strip tracker, a lead tungstate crystal electromagnetic calorimeter, and a brass and scintillator hadron calorimeter. Muons are measured in gas-ionization detectors embedded in the steel return yoke. The central detectors of CMS are complemented by calorimeters in the forward direction, which all rely on the detection of Cherenkov photons produced when charged particles pass through their active quartz components. The “hadron forward” (HF) calorimeters cover the pseudorapidity interval 3.0 < |η| < 5.2 and use quartz fibers embedded in a steel absorber. The CASTOR calorimeter is a sampling calorimeter composed of layers of fused silica quartz plates and tungsten absorbers, segmented in 16 azimuthal towers, each with 14 longitudinal channels. The two front channels have a combined depth of 20 radiation lengths and form the electromagnetic section of each tower. The remaining 12 channels constitute the hadronic section. The full depth of a tower amounts to 10 hadronic interaction lengths. A more detailed description of the CMS detector, together with a definition of the coordinate system used and all relevant kinematic variables, can be found in Ref. [15]. For triggering purposes, the Beam Pickup Timing for the eXperiment device was used [16]. The corrections to the level of stable particles with cτ > 1 cm are determined by means of a Monte Carlo (MC) simulation of the CMS apparatus based on GEANT4 [17], including all 2 3 Event selection and data analysis known information about the CASTOR detector.

The data are compared to model predictions from PYTHIA 8 [18] (version 8.212) with tune CUETP8M1√ [19], which is based on measurements of the underlying event in pp¯ and pp collisions at s = 1.96 and 7 TeV, and tune 4C [4] combined with the MBR [20] model to describe diffractive processes. The PYTHIA 8 CUETP8M1 tunes use the NNPDF2.3LO [21] parton distribution functions (PDF), whereas tune 4C uses the CTEQ6L1 PDF [22]. Hadronic interaction event generators mostly developed for cosmic ray physics are also used: EPOS LHC [23] and its previous version EPOS 1.99 [24], QGSJETII [25] version II.3 and II.4, as well as SIBYLL 2.1 [26] and the recently√ released SIBYLL 2.3 [27]. The latest versions of all these models are tuned to LHC data up to s = 8 TeV, while the earlier versions are tuned to Tevatron results [28].

3 Event selection and data analysis The present analysis is based on data that were recorded during the low luminosity LHC Run in 2015, when CASTOR was operational and the CMS solenoid was off. The data correspond to an integrated luminosity of 0.34 µb−1, with an average pp interaction probability of 5% per bunch crossing. Data were recorded with an unbiased trigger requiring only the presence of two colliding bunches. Electronic noise and beam-induced backgrounds are studied with data taken without colliding bunches. Events are selected ofﬂine by requiring hadronic activity in the HF calorimeters on either side of CMS. At least one reconstructed calorimeter tower with energy larger than 5 GeV is required. With these selection criteria the residual contribution of electronic noise and beam background is well below 1%. Beam halo muons are used to determine the calibration of each CASTOR channel relative to the others. This inter-calibration procedure cannot be applied to the last two longitudinal channels, which have detector noise levels very close to the muon ionization peak and are not included in the dedicated halo-muon trigger. These channels are therefore excluded from the analysis. The response of CASTOR to pions and electrons was measured in a test beam in 2008 [29]. However, the conﬁguration of CASTOR changed since then. Because of this, an independent method based on 7 TeV collision data is used to determine the absolute energy scale calibration of CASTOR. The average energy measured by the HF calorimeters in the region 3 < |η| < 5 is fully corrected to the particle level [30] and extrapolated to the region covered by CASTOR, using various hadronic interaction models. The result of the extrapolation is used to calibrate CASTOR. The detector response is found to be consistent with the test beam results. Such a data-driven method facilitates the assignment of a realistic uncertainty on the calorimeters energy scale. In order to reconstruct the total energy deposited in CASTOR, the energies of all calorimeter towers above the noise threshold are summed up. This threshold is determined indepen- dently for every calorimeter tower and varies between 2 and 2.5 GeV. The electromagnetic and hadronic contributions to the total energy can be determined by using the corresponding sections of CASTOR. The measured detector-level spectra are shown in Fig. 1. Differences among model predictions are apparent. The correction to the particle level is carried out through an unfolding technique by means of the ROOUNFOLD package [31] with the iterative algorithm proposed by D’Agostini [32]. The procedure is stopped after 4 (6, 5) iterations for the total (electromagnetic, hadronic) spectrum, when the change with respect to the previous step is less than one percent. Figure 2 shows the distributions of reconstructed energy in CASTOR as a function of the true energy at particle 3

-6.6 < η < -5.2 0.34 µb-1 (13 TeV) -6.6 < η < -5.2 0.34 µb-1 (13 TeV) -6.6 < η < -5.2 0.34 µb-1 (13 TeV) 10−1 10−1 10−1 CMS PYTHIA8 CUETP8M1 CMS PYTHIA8 CUETP8M1 CMS PYTHIA8 CUETP8M1 10−2 PYTHIA8 4C+MBR 10−2 PYTHIA8 4C+MBR 10−2 PYTHIA8 4C+MBR EPOS LHC EPOS LHC EPOS LHC − − − 10 3 10 3 10 3

10−4 10−4 10−4 dN/dE (1/GeV) dN/dE (1/GeV) dN/dE (1/GeV) − − − evt 10 5 evt 10 5 evt 10 5 Data Data Data

1/N − 1/N − 1/N − 10 6 Total uncertainty 10 6 Total uncertainty 10 6 Total uncertainty

10−7 10−7 10−7 2 2 2

1 1 1

MC/Data 0 MC/Data 0 MC/Data 0 0 500 1000 1500 2000 2500 3000 0 500 1000 1500 2000 0 500 1000 1500 Uncorrected total energy (GeV) Uncorrected em. energy (GeV) Uncorrected had. energy (GeV) Figure 1: Spectra of the energy reconstructed in CASTOR, normalized to the number of events that pass the offline event selection, compared to the detector-level predictions of various event generators. The total energy spectrum is shown in the left panel, the electromagnetic in the middle, and the hadronic in the right. Statistical (systematic) uncertainties are shown with error bars (yellow band, discussed in Section 4). level for PYTHIA 8 CUETP8M1. The fact that the slope of the correlation for the hadronic energy is not unity reflects the noncompensating nature of the calorimeter. The event selection at particle level is based on the Lorentz-invariant fractional momentum loss of the proton, ξ. All final-state particles are divided into two systems, X and Y, based on their rapidity with respect to the pair of particles with the largest separation in rapidity. All particles on the negative side of this gap are assigned to the system X, while the particles on the positive side are assigned to the system Y [8]. The invariant masses, MX and MY, of each system are calculated using the four-momenta of the individual particles, and the variable ξ is defined as the maximum of their squared ratios to the center-of-mass energy:

2 2 ξX = M /s, ξY = M /s, and X Y (1) ξ = max(ξX, ξY).

The variable ξ, commonly used to describe diffractive processes, is well defined for any pp final-state and provides a particularly economical particle-level description of the phase space acceptance at forward rapidities, independent of the underlying particle production mecha- nism. Events with ξ > 10−6 at particle level are selected, with an efficiency of about 97.3% and a purity of about 99.5% with respect to the detector-level event selection. The total energy at particle level is calculated by summing up the energies of all particles, except muons and neutrinos, within the acceptance of CASTOR. Muons and neutrinos are excluded since they do not deposit relevant energies in the detector. For the electromagnetic spectrum, only electrons and photons are used; the latter are excluded for the hadronic energy spectrum. The decay photons of neutral pions constitute the dominant contribution to the electromagnetic spectrum.

4 Experimental uncertainties and results The experimental uncertainties of the present results are mainly of systematic nature, with the CASTOR energy scale uncertainty being the most signiﬁcant contribution. In the data- driven calibration method, uncertainties on the energy scale arise from the HF energy scale uncertainty, the extrapolation uncertainty, and the noncompensating calorimetric response of CASTOR. Furthermore, the energy measured by CASTOR depends on its exact location with respect to the interaction point. This is because the energy ﬂow dE/dη rises sharply with η 4 4 Experimental uncertainties and results

-6.6 < η < -5.2 , ξ >10-6 (13 TeV) -6.6 < η < -5.2 , ξ >10-6 (13 TeV) -6.6 < η < -5.2 , ξ >10-6 (13 TeV) 8 3.5 7 10 CMS Simulation CMS Simulation CMS Simulation 7 3 6 8 6 2.5 5 5 6 2 4 Events (x1000) 4 1.5 3 3 4 1 2 2

Generator em. energy (TeV) 2 Generator total energy (TeV) 1 0.5 Generator had. energy (TeV) 1 0 0 0 0 0 1 2 3 4 5 6 7 8 0 0.5 1 1.5 2 2.5 3 3.5 0 1 2 3 4 5 6 7 Reconstructed total energy (TeV) Reconstructed em. energy (TeV) Reconstructed had. energy (TeV) Figure 2: Distributions of reconstructed energy as a function of the particle-level energy for PYTHIA 8 CUETP8M1 for the total (left), electromagnetic (middle), and hadronic (right) energy in CASTOR. The color indicates the number of events. The selection ξ > 10−6 is explained in the text. in the very forward region. For the present data, the position of CASTOR is known to within 1 mm, leading to a 7.5% energy scale uncertainty. This is determined by means of Monte Carlo studies in which CASTOR is moved within the measurement uncertainties. All contributions to the energy scale uncertainty add up to 17% at detector level. An additional systematic uncertainty comes from the inter-calibration of the channels with respect to each other. This affects the separation of the electromagnetic and hadronic energies by up to 16%. The sensitivity of the result to the event selection based on activity in HF is quantified by vary- ing by 10% the 5 GeV selection threshold, which corresponds to the energy scale uncertainty of the HF calorimeters. The effect is below 6.2% for the total energy, and less for the electromagnetic and hadronic energies. Other sources of uncertainties, such as noise, beam background, or pileup are found to be negligible. The detector-level spectra are varied within each of the above uncertainties, and then unfolded. The spread of the unfolded spectra is then taken as a measure of the systematic uncertainty associated to each distribution. Since the unfolding relies on Monte Carlo simulation, three models are used to unfold the detector-level spectra: PYTHIA 8 4C+MBR, PYTHIA 8 CUETP8M1, and EPOS LHC. The average of the resulting spectra is used as the nominal result and half their spread as an additional model-dependent systematic uncertainty. This uncertainty is below 20% for the total and electromagnetic spectra. The model dependence for the hadronic energy is higher and reaches 63% in some energy bins. These uncertainties increase with energy. The luminosity recorded by CMS is determined with a precision of 2.3% for data taken with full magnetic field [33]. The luminosity at zero magnetic field can be recalibrated by comparing full and zero field data directly; the corresponding uncertainty is 2.6%. All contributions to the systematic uncertainties are added in quadrature. Example values are given for two bins of total, hadronic, and electromagnetic energies in Table 1. The statistical uncertainties are calculated with the full covariance matrices of the unfolded results and therefore include correlations induced by the unfolding procedure. The full covariance matrices are available in the HEPDATA record of this paper; the differential cross section measurements with uncertainties are also tabulated therein [34]. In the figures, the total uncertainties are shown as yellow bands; they include the statistical uncertainties, which in most bins are not visible. The uncertainty assigned to the model dependence of the unfolding procedure is shown as an orange band. 5

Table 1: Uncertainties on the differential cross sections at a few selected values of the total, electromagnetic, and hadronic energies. Total Electromagnetic Hadronic 300 GeV 3000 GeV 300 GeV 1200 GeV 300 GeV 2000 GeV +17 % +94 % +5.9 % +93 % +11 % +169 % Energy Scale −14 % −77 % −2.1 % −65 % −10 % −80 % Unfolding ±5.8% ±6.4% ±5.2% ±4.1% ±6.9% ±17% Event selection ±0.5% <0.01% ±0.14% <0.01% ±0.06% <0.01% Luminosity ±2.6% Statistical ±1.2% ±4.3% ±1.5% ±5.9% ±1.0% ±4.2%

The total, electromagnetic, and hadronic energy spectra are measured in the region −6.6 < η < −5.2 and corrected to the particle level for ξ > 10−6. They are shown in Figs. 3–5 and compared to the predictions of EPOS,QGSJETII and SIBYLL (left plots) and various PYTHIA 8 tunes (right plots). All spectra feature a sharp peak at zero reﬂecting the presence of diffractive events with forward rapidity gap(s). The total and hadronic energy spectra exhibit peaks at about 300 and 100 GeV respectively, followed by a long tail towards higher energies. Such a peak is not observed in the electromagnetic spectrum. In Fig. 3, the distribution of the total energy is shown. Different parts of the spectrum are reproduced by different models. None of the models reproduce all features of the data, but the bump at about 300 GeV is visible in all of them. The spectrum is best described by EPOS LHC and QGSJETII.4. The PYTHIA 8 tunes tend to overestimate the contribution of the soft part of the spectrum and so does SIBYLL 2.3. The high energy tail is well described by PYTHIA 8 and SIBYLL, whereas EPOS LHC and QGSJETII.4 overestimate the region between 1 and ref 2.5 TeV. The predictions are also very sensitive to the scaling parameter pT,0 of PYTHIA 8, which parameterizes the dampening of the partonic cross sections for pT → 0 at the nominal reference ref energy of 7 TeV [18]. Large deviations from the CUETP8M1 pT,0 default value of 2.4024 GeV modify the simulation of MPI and lead to predictions inconsistent with the data; the PDF choice (NNPDF2.3 in CUETP8M1 versus CTEQ6L1 in 4C) and/or the diffraction model used (MBR or default PYTHIA 8 model) also play a role in some regions of phase space. The electromagnetic spectrum is shown in Fig. 4; it is relatively well described by most of the models within uncertainties. Only PYTHIA 8 4C+MBR and SIBYLL 2.3 do not correctly model the shape of the soft part of the spectrum up to about 500 GeV. The comparison of the data to the predictions of various PYTHIA 8 tunes indicates that the electromagnetic energy distribution is also very sensitive to the underlying modeling of MPI.

Figure 5 shows the hadronic energy distribution. While EPOS LHC and QGSJETII perform well at lower energies, they predict too large a cross section in the range of 600 to 1800 GeV. This feature is also observed in the total energy spectrum, suggesting that the excess originates from the production of hadrons. SIBYLL 2.3 reproduces the slope of the spectrum over a larger energy range, but signiﬁcantly overestimates the cross section at very low energy, while SIBYLL 2.1 shows a large excess at around 500 GeV, similar to that observed in the total energy spectrum.

5 Summary The electromagnetic, hadronic, and total energy spectra of particles produced at very forward pseudorapidities (−6.6 < η < −5.2) have been measured with the CASTOR calorimeter of the CMS experiment in proton-proton collisions at a center-of-mass energy of 13 TeV. The ex- 6 5 Summary

-6.6 < η < -5.2 , ξ >10-6 0.34 µb-1 (13 TeV) -6.6 < η < -5.2 , ξ >10-6 0.34 µb-1 (13 TeV) 103 103 CMS EPOS LHC CMS PYTHIA8 CUETP8M1 EPOS 1.99 PYTHIA8 CUETP8M1, no MPI PYTHIA8 CUETP8M1, pt0Ref=1.5 2 Sibyll 2.3 2 b/GeV) 10 Sibyll 2.1 b/GeV) 10 PYTHIA8 CUETP8M1, pt0Ref=3.0 µ QGSJet II.04 µ PYTHIA8 4C+MBR QGSJet II.03

/dE ( 10 /dE ( 10 σ σ d d

1 1

Data Data 10−1 Total uncertainty 10−1 Total uncertainty Model uncertainty Model uncertainty

10−2 10−2 2 2

1 1 MC/Data MC/Data 0 0 0 1000 2000 3000 4000 5000 0 1000 2000 3000 4000 5000 Total energy (GeV) Total energy (GeV) Figure 3: Differential cross section as a function of the total energy in the region −6.6 < η < −5.2 for events with ξ > 10−6. The left panel shows the data compared to MC event generators mostly developed for cosmic ray induced air showers, and the right panel to different PYTHIA 8 tunes.

/dE ( 10 /dE ( 10 σ σ d d

1 1

Data Data 10−1 Total uncertainty 10−1 Total uncertainty Model uncertainty Model uncertainty

10−2 10−2 2 2

1 1 MC/Data MC/Data 0 0 0 500 1000 1500 2000 0 500 1000 1500 2000 Electromagnetic energy (GeV) Electromagnetic energy (GeV) Figure 4: Differential cross section as a function of the electromagnetic energy in the region −6.6 < η < −5.2 for events with ξ > 10−6. The left panel shows the data compared to MC event generators mostly developed for cosmic ray induced air showers, and the right panel to different PYTHIA 8 tunes. 7

-6.6 < η < -5.2 , ξ >10-6 0.34 µb-1 (13 TeV) -6.6 < η < -5.2 , ξ >10-6 0.34 µb-1 (13 TeV) 105 105 PYTHIA8 CUETP8M1 4 CMS EPOS LHC 4 CMS 10 EPOS 1.99 10 PYTHIA8 CUETP8M1, no MPI 3 Sibyll 2.3 3 PYTHIA8 CUETP8M1, pt0Ref=1.5

b/GeV) 10 b/GeV) 10 Sibyll 2.1 PYTHIA8 CUETP8M1, pt0Ref=3.0 µ 102 QGSJet II.04 µ 102 PYTHIA8 4C+MBR QGSJet II.03 10 10 /dE ( /dE ( σ σ

d 1 d 1 10−1 10−1 10−2 10−2 − − 10 3 Data 10 3 Data Total uncertainty Total uncertainty 10−4 10−4 Model uncertainty Model uncertainty − − 10 5 10 5 − − 10 6 10 6 2 2

1 1 MC/Data MC/Data 0 0 0 1000 2000 3000 4000 5000 0 1000 2000 3000 4000 5000 Hadronic energy (GeV) Hadronic energy (GeV) Figure 5: Differential cross section as a function of the hadronic energy in the region −6.6 < η < −5.2 for events with ξ > 10−6. The left panel shows the data compared to MC event generators mostly developed for cosmic ray induced air showers, and the right panel to different PYTHIA 8 tunes. perimental distributions, fully corrected for detector effects, are compared to the predictions of various Monte Carlo event generators commonly used in high energy cosmic ray physics (EPOS,QGSJETII, and SIBYLL), and those of different tunes of PYTHIA 8. None of the generators considered describe all features seen in the data. The present measurements are particularly sensitive to the modeling of multiparton interactions (MPI) that dominate particle production in the underlying event at forward rapidities in pp collisions. PYTHIA 8 CUETP8M1 without MPI is ruled out by the data, which exhibit much harder spectra than predicted by the model. The shape of the spectra are signiﬁcantly inﬂu- enced by the MPI-related settings in PYTHIA 8. The present results can therefore contribute to improvements in future Monte Carlo parameter tunes. Event generators developed for modeling high energy cosmic ray air showers, tuned to LHC measurements at 0.9, 7, and 8 TeV, agree better with the present data than those tuned to Teva- tron results alone. This is especially true for QGSJETII and SIBYLL. However, all these models underestimate the muon production rate in extensive air showers because of their inaccurate description of the hadronic shower component [35]. The present results provide new constraints for improving the modeling of hadron production in event generators commonly used in high energy particle and cosmic ray physics.

Acknowledgments We congratulate our colleagues in the CERN accelerator departments for the excellent performance of the LHC and thank the technical and administrative staffs at CERN and at other CMS institutes for their contributions to the success of the CMS effort. In addition, we grate- fully acknowledge the computing centers and personnel of the Worldwide LHC Computing Grid for delivering so effectively the computing infrastructure essential to our analyses. Fi- nally, we acknowledge the enduring support for the construction and operation of the LHC and the CMS detector provided by the following funding agencies: BMWFW and FWF (Aus- 8 References tria); FNRS and FWO (Belgium); CNPq, CAPES, FAPERJ, and FAPESP (Brazil); MES (Bulgaria); CERN; CAS, MoST, and NSFC (China); COLCIENCIAS (Colombia); MSES and CSF (Croatia); RPF (Cyprus); SENESCYT (Ecuador); MoER, ERC IUT, and ERDF (Estonia); Academy of Fin- land, MEC, and HIP (Finland); CEA and CNRS/IN2P3 (France); BMBF, DFG, and HGF (Ger- many); GSRT (Greece); OTKA and NIH (Hungary); DAE and DST (India); IPM (Iran); SFI (Ireland); INFN (Italy); MSIP and NRF (Republic of Korea); LAS (Lithuania); MOE and UM (Malaysia); BUAP, CINVESTAV, CONACYT, LNS, SEP, and UASLP-FAI (Mexico); MBIE (New Zealand); PAEC (Pakistan); MSHE and NSC (Poland); FCT (Portugal); JINR (Dubna); MON, RosAtom, RAS, RFBR and RAEP (Russia); MESTD (Serbia); SEIDI, CPAN, PCTI and FEDER (Spain); Swiss Funding Agencies (Switzerland); MST (Taipei); ThEPCenter, IPST, STAR, and NSTDA (Thailand); TUBITAK and TAEK (Turkey); NASU and SFFR (Ukraine); STFC (United Kingdom); DOE and NSF (USA). Individuals have received support from the Marie-Curie program and the European Research Council and EPLANET (European Union); the Leventis Foundation; the A. P. Sloan Founda- tion; the Alexander von Humboldt Foundation; the Belgian Federal Science Policy Office; the Fonds pour la Formation a` la Recherche dans l’Industrie et dans l’Agriculture (FRIA-Belgium); the Agentschap voor Innovatie door Wetenschap en Technologie (IWT-Belgium); the Ministry of Education, Youth and Sports (MEYS) of the Czech Republic; the Council of Science and In- dustrial Research, India; the HOMING PLUS program of the Foundation for Polish Science, cofinanced from European Union, Regional Development Fund, the Mobility Plus program of the Ministry of Science and Higher Education, the National Science Center (Poland), contracts Harmonia 2014/14/M/ST2/00428, Opus 2014/13/B/ST2/02543, 2014/15/B/ST2/03998, and 2015/19/B/ST2/02861, Sonata-bis 2012/07/E/ST2/01406; the National Priorities Research Pro- gram by Qatar National Research Fund; the Programa Clar´ın-COFUND del Principado de Asturias; the Thalis and Aristeia programs cofinanced by EU-ESF and the Greek NSRF; the Rachadapisek Sompot Fund for Postdoctoral Fellowship, Chulalongkorn University and the Chulalongkorn Academic into Its 2nd Century Project Advancement Project (Thailand); and the Welch Foundation, contract C-1845.

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A The CMS Collaboration Yerevan Physics Institute, Yerevan, Armenia A.M. Sirunyan, A. Tumasyan Institut f ürHochenergiephysik, Wien, Austria W. Adam, E. Asilar, T. Bergauer, J. Brandstetter, E. Brondolin, M. Dragicevic, J. Ero,¨ M. Flechl, M. Friedl, R. Fruhwirth¨ 1, V.M. Ghete, C. Hartl, N. Hormann,¨ J. Hrubec, M. Jeitler1, A. Konig,¨ I. Kratschmer,¨ D. Liko, T. Matsushita, I. Mikulec, D. Rabady, N. Rad, B. Rahbaran, H. Rohringer, J. Schieck1, J. Strauss, W. Waltenberger, C.-E. Wulz1 Institute for Nuclear Problems, Minsk, Belarus O. Dvornikov, V. Makarenko, V. Mossolov, J. Suarez Gonzalez, V. Zykunov National Centre for Particle and High Energy Physics, Minsk, Belarus N. Shumeiko Universiteit Antwerpen, Antwerpen, Belgium S. Alderweireldt, E.A. De Wolf, X. Janssen, J. Lauwers, M. Van De Klundert, H. Van Haevermaet, P. Van Mechelen, N. Van Remortel, A. Van Spilbeeck Vrije Universiteit Brussel, Brussel, Belgium S. Abu Zeid, F. Blekman, J. D’Hondt, N. Daci, I. De Bruyn, K. Deroover, S. Lowette, S. Moortgat, L. Moreels, A. Olbrechts, Q. Python, K. Skovpen, S. Tavernier, W. Van Doninck, P. Van Mulders, I. Van Parijs UniversitéLibre de Bruxelles, Bruxelles, Belgium H. Brun, B. Clerbaux, G. De Lentdecker, H. Delannoy, G. Fasanella, L. Favart, R. Goldouzian, A. Grebenyuk, G. Karapostoli, T. Lenzi, A. Leonard,´ J. Luetic, T. Maerschalk, A. Marinov, A. Randle-conde, T. Seva, C. Vander Velde, P. Vanlaer, D. Vannerom, R. Yonamine, F. Zenoni, F. Zhang2 Ghent University, Ghent, Belgium A. Cimmino, T. Cornelis, D. Dobur, A. Fagot, M. Gul, I. Khvastunov, D. Poyraz, S. Salva, R. Schofbeck,¨ M. Tytgat, W. Van Driessche, E. Yazgan, N. Zaganidis UniversitéCatholique de Louvain, Louvain-la-Neuve, Belgium H. Bakhshiansohi, C. Beluffi3, O. Bondu, S. Brochet, G. Bruno, A. Caudron, S. De Visscher, C. Delaere, M. Delcourt, B. Francois, A. Giammanco, A. Jafari, M. Komm, G. Krintiras, V. Lemaitre, A. Magitteri, A. Mertens, M. Musich, K. Piotrzkowski, L. Quertenmont, M. Selvaggi, M. Vidal Marono, S. Wertz Universitéde Mons, Mons, Belgium N. Beliy Centro Brasileiro de Pesquisas Fisicas, Rio de Janeiro, Brazil W.L. Alda´ Junior,´ F.L. Alves, G.A. Alves, L. Brito, C. Hensel, A. Moraes, M.E. Pol, P. Rebello Teles Universidade do Estado do Rio de Janeiro, Rio de Janeiro, Brazil E. Belchior Batista Das Chagas, W. Carvalho, J. Chinellato4, A. Custodio,´ E.M. Da Costa, G.G. Da Silveira5, D. De Jesus Damiao, C. De Oliveira Martins, S. Fonseca De Souza, L.M. Huertas Guativa, H. Malbouisson, D. Matos Figueiredo, C. Mora Herrera, L. Mundim, H. Nogima, W.L. Prado Da Silva, A. Santoro, A. Sznajder, E.J. Tonelli Manganote4, F. Torres Da Silva De Araujo, A. Vilela Pereira 14 A The CMS Collaboration

Universidade Estadual Paulista a, Universidade Federal do ABC b, SãoPaulo, Brazil S. Ahujaa, C.A. Bernardesa, S. Dograa, T.R. Fernandez Perez Tomeia, E.M. Gregoresb, P.G. Mercadanteb, C.S. Moona, S.F. Novaesa, Sandra S. Padulaa, D. Romero Abadb, J.C. Ruiz Vargasa Institute for Nuclear Research and Nuclear Energy, Sofia, Bulgaria A. Aleksandrov, R. Hadjiiska, P. Iaydjiev, M. Rodozov, S. Stoykova, G. Sultanov, M. Vutova University of Sofia, Sofia, Bulgaria A. Dimitrov, I. Glushkov, L. Litov, B. Pavlov, P. Petkov Beihang University, Beijing, China W. Fang6 Institute of High Energy Physics, Beijing, China M. Ahmad, J.G. Bian, G.M. Chen, H.S. Chen, M. Chen, Y. Chen7, T. Cheng, C.H. Jiang, D. Leggat, Z. Liu, F. Romeo, M. Ruan, S.M. Shaheen, A. Spiezia, J. Tao, C. Wang, Z. Wang, H. Zhang, J. Zhao State Key Laboratory of Nuclear Physics and Technology, Peking University, Beijing, China Y. Ban, G. Chen, Q. Li, S. Liu, Y. Mao, S.J. Qian, D. Wang, Z. Xu Universidad de Los Andes, Bogota, Colombia C. Avila, A. Cabrera, L.F. Chaparro Sierra, C. Florez, J.P. Gomez, C.F. Gonzalez´ Hernandez,´ J.D. Ruiz Alvarez, J.C. Sanabria University of Split, Faculty of Electrical Engineering, Mechanical Engineering and Naval Architecture, Split, Croatia N. Godinovic, D. Lelas, I. Puljak, P.M. Ribeiro Cipriano, T. Sculac University of Split, Faculty of Science, Split, Croatia Z. Antunovic, M. Kovac Institute Rudjer Boskovic, Zagreb, Croatia V. Brigljevic, D. Ferencek, K. Kadija, B. Mesic, T. Susa University of Cyprus, Nicosia, Cyprus A. Attikis, G. Mavromanolakis, J. Mousa, C. Nicolaou, F. Ptochos, P.A. Razis, H. Rykaczewski, D. Tsiakkouri Charles University, Prague, Czech Republic M. Finger8, M. Finger Jr.8 Universidad San Francisco de Quito, Quito, Ecuador E. Carrera Jarrin Academy of Scientific Research and Technology of the Arab Republic of Egypt, Egyptian Network of High Energy Physics, Cairo, Egypt A.A. Abdelalim9,10, Y. Mohammed11, E. Salama12,13 National Institute of Chemical Physics and Biophysics, Tallinn, Estonia M. Kadastik, L. Perrini, M. Raidal, A. Tiko, C. Veelken Department of Physics, University of Helsinki, Helsinki, Finland P. Eerola, J. Pekkanen, M. Voutilainen 15

Helsinki Institute of Physics, Helsinki, Finland J. Hark¨ onen,¨ T. Jarvinen,¨ V. Karimaki,¨ R. Kinnunen, T. Lampen,´ K. Lassila-Perini, S. Lehti, T. Linden,´ P. Luukka, J. Tuominiemi, E. Tuovinen, L. Wendland Lappeenranta University of Technology, Lappeenranta, Finland J. Talvitie, T. Tuuva IRFU, CEA, UniversitéParis-Saclay, Gif-sur-Yvette, France M. Besancon, F. Couderc, M. Dejardin, D. Denegri, B. Fabbro, J.L. Faure, C. Favaro, F. Ferri, S. Ganjour, S. Ghosh, A. Givernaud, P. Gras, G. Hamel de Monchenault, P. Jarry, I. Kucher, E. Locci, M. Machet, J. Malcles, J. Rander, A. Rosowsky, M. Titov Laboratoire Leprince-Ringuet, Ecole Polytechnique, IN2P3-CNRS, Palaiseau, France A. Abdulsalam, I. Antropov, S. Baffioni, F. Beaudette, P. Busson, L. Cadamuro, E. Chapon, C. Charlot, O. Davignon, R. Granier de Cassagnac, M. Jo, S. Lisniak, P. Mine,´ M. Nguyen, C. Ochando, G. Ortona, P. Paganini, P. Pigard, S. Regnard, R. Salerno, Y. Sirois, A.G. Stahl Leiton, T. Strebler, Y. Yilmaz, A. Zabi, A. Zghiche Institut Pluridisciplinaire Hubert Curien (IPHC), Universitéde Strasbourg, CNRS-IN2P3 J.-L. Agram14, J. Andrea, A. Aubin, D. Bloch, J.-M. Brom, M. Buttignol, E.C. Chabert, N. Chanon, C. Collard, E. Conte14, X. Coubez, J.-C. Fontaine14, D. Gele,´ U. Goerlach, A.-C. Le Bihan, P. Van Hove Centre de Calcul de l’Institut National de Physique Nucleaire et de Physique des Particules, CNRS/IN2P3, Villeurbanne, France S. Gadrat Universitéde Lyon, UniversitéClaude Bernard Lyon 1, CNRS-IN2P3, Institut de Physique Nucléairede Lyon, Villeurbanne, France S. Beauceron, C. Bernet, G. Boudoul, C.A. Carrillo Montoya, R. Chierici, D. Contardo, B. Courbon, P. Depasse, H. El Mamouni, J. Fay, S. Gascon, M. Gouzevitch, G. Grenier, B. Ille, F. Lagarde, I.B. Laktineh, M. Lethuillier, L. Mirabito, A.L. Pequegnot, S. Perries, A. Popov15, D. Sabes, V. Sordini, M. Vander Donckt, P. Verdier, S. Viret Georgian Technical University, Tbilisi, Georgia T. Toriashvili16 Tbilisi State University, Tbilisi, Georgia Z. Tsamalaidze8 RWTH Aachen University, I. Physikalisches Institut, Aachen, Germany C. Autermann, S. Beranek, L. Feld, M.K. Kiesel, K. Klein, M. Lipinski, M. Preuten, C. Schomakers, J. Schulz, T. Verlage RWTH Aachen University, III. Physikalisches Institut A, Aachen, Germany A. Albert, M. Brodski, E. Dietz-Laursonn, D. Duchardt, M. Endres, M. Erdmann, S. Erdweg, T. Esch, R. Fischer, A. Guth,¨ M. Hamer, T. Hebbeker, C. Heidemann, K. Hoepfner, S. Knutzen, M. Merschmeyer, A. Meyer, P. Millet, S. Mukherjee, M. Olschewski, K. Padeken, T. Pook, M. Radziej, H. Reithler, M. Rieger, F. Scheuch, L. Sonnenschein, D. Teyssier, S. Thuer¨ RWTH Aachen University, III. Physikalisches Institut B, Aachen, Germany V. Cherepanov, G. Flugge,¨ B. Kargoll, T. Kress, A. Kunsken,¨ J. Lingemann, T. Muller,¨ A. Nehrkorn, A. Nowack, C. Pistone, O. Pooth, A. Stahl17 16 A The CMS Collaboration

Deutsches Elektronen-Synchrotron, Hamburg, Germany M. Aldaya Martin, T. Arndt, C. Asawatangtrakuldee, K. Beernaert, O. Behnke, U. Behrens, A.A. Bin Anuar, K. Borras18, A. Campbell, P. Connor, C. Contreras-Campana, F. Costanza, C. Diez Pardos, G. Dolinska, G. Eckerlin, D. Eckstein, T. Eichhorn, E. Eren, E. Gallo19, J. Garay Garcia, A. Geiser, A. Gizhko, J.M. Grados Luyando, A. Grohsjean, P. Gunnellini, A. Harb, J. Hauk, M. Hempel20, H. Jung, A. Kalogeropoulos, O. Karacheban20, M. Kasemann, J. Keaveney, C. Kleinwort, I. Korol, D. Krucker,¨ W. Lange, A. Lelek, T. Lenz, J. Leonard, K. Lipka, A. Lobanov, W. Lohmann20, R. Mankel, I.-A. Melzer-Pellmann, A.B. Meyer, G. Mittag, J. Mnich, A. Mussgiller, D. Pitzl, R. Placakyte, A. Raspereza, B. Roland, M.O.¨ Sahin, P. Saxena, T. Schoerner-Sadenius, S. Spannagel, N. Stefaniuk, G.P. Van Onsem, R. Walsh, C. Wissing University of Hamburg, Hamburg, Germany V. Blobel, M. Centis Vignali, A.R. Draeger, T. Dreyer, E. Garutti, D. Gonzalez, J. Haller, M. Hoffmann, A. Junkes, R. Klanner, R. Kogler, N. Kovalchuk, T. Lapsien, I. Marchesini, D. Marconi, M. Meyer, M. Niedziela, D. Nowatschin, F. Pantaleo17, T. Peiffer, A. Perieanu, C. Scharf, P. Schleper, A. Schmidt, S. Schumann, J. Schwandt, H. Stadie, G. Steinbruck,¨ F.M. Stober, M. Stover,¨ H. Tholen, D. Troendle, E. Usai, L. Vanelderen, A. Vanhoefer, B. Vormwald Institut f ürExperimentelle Kernphysik, Karlsruhe, Germany M. Akbiyik, C. Barth, S. Baur, C. Baus, J. Berger, E. Butz, R. Caspart, T. Chwalek, F. Colombo, W. De Boer, A. Dierlamm, S. Fink, B. Freund, R. Friese, M. Giffels, A. Gilbert, P. Goldenzweig, D. Haitz, F. Hartmann17, S.M. Heindl, U. Husemann, I. Katkov15, S. Kudella, H. Mildner, M.U. Mozer, Th. Muller,¨ M. Plagge, G. Quast, K. Rabbertz, S. Rocker,¨ F. Roscher, M. Schroder,¨ I. Shvetsov, G. Sieber, H.J. Simonis, R. Ulrich, S. Wayand, M. Weber, T. Weiler, S. Williamson, C. Wohrmann,¨ R. Wolf Institute of Nuclear and Particle Physics (INPP), NCSR Demokritos, Aghia Paraskevi, Greece G. Anagnostou, G. Daskalakis, T. Geralis, V.A. Giakoumopoulou, A. Kyriakis, D. Loukas, I. Topsis-Giotis National and Kapodistrian University of Athens, Athens, Greece S. Kesisoglou, A. Panagiotou, N. Saoulidou, E. Tziaferi University of Ioánnina,Ioánnina,Greece I. Evangelou, G. Flouris, C. Foudas, P. Kokkas, N. Loukas, N. Manthos, I. Papadopoulos, E. Paradas MTA-ELTE Lend ületCMS Particle and Nuclear Physics Group, EötvösLorándUniversity, Budapest, Hungary N. Filipovic, G. Pasztor Wigner Research Centre for Physics, Budapest, Hungary G. Bencze, C. Hajdu, D. Horvath21, F. Sikler, V. Veszpremi, G. Vesztergombi22, A.J. Zsigmond Institute of Nuclear Research ATOMKI, Debrecen, Hungary N. Beni, S. Czellar, J. Karancsi23, A. Makovec, J. Molnar, Z. Szillasi Institute of Physics, University of Debrecen M. Bartok´ 22, P. Raics, Z.L. Trocsanyi, B. Ujvari Indian Institute of Science (IISc) J.R. Komaragiri 17

National Institute of Science Education and Research, Bhubaneswar, India S. Bahinipati24, S. Bhowmik25, S. Choudhury26, P. Mal, K. Mandal, A. Nayak27, D.K. Sahoo24, N. Sahoo, S.K. Swain Panjab University, Chandigarh, India S. Bansal, S.B. Beri, V. Bhatnagar, R. Chawla, U.Bhawandeep, A.K. Kalsi, A. Kaur, M. Kaur, R. Kumar, P. Kumari, A. Mehta, M. Mittal, J.B. Singh, G. Walia University of Delhi, Delhi, India Ashok Kumar, A. Bhardwaj, B.C. Choudhary, R.B. Garg, S. Keshri, S. Malhotra, M. Naimuddin, K. Ranjan, R. Sharma, V. Sharma Saha Institute of Nuclear Physics, Kolkata, India R. Bhattacharya, S. Bhattacharya, K. Chatterjee, S. Dey, S. Dutt, S. Dutta, S. Ghosh, N. Majumdar, A. Modak, K. Mondal, S. Mukhopadhyay, S. Nandan, A. Purohit, A. Roy, D. Roy, S. Roy Chowdhury, S. Sarkar, M. Sharan, S. Thakur Indian Institute of Technology Madras, Madras, India P.K. Behera Bhabha Atomic Research Centre, Mumbai, India R. Chudasama, D. Dutta, V. Jha, V. Kumar, A.K. Mohanty17, P.K. Netrakanti, L.M. Pant, P. Shukla, A. Topkar Tata Institute of Fundamental Research-A, Mumbai, India T. Aziz, S. Dugad, G. Kole, B. Mahakud, S. Mitra, G.B. Mohanty, B. Parida, N. Sur, B. Sutar Tata Institute of Fundamental Research-B, Mumbai, India S. Banerjee, R.K. Dewanjee, S. Ganguly, M. Guchait, Sa. Jain, S. Kumar, M. Maity25, G. Majumder, K. Mazumdar, T. Sarkar25, N. Wickramage28 Indian Institute of Science Education and Research (IISER), Pune, India S. Chauhan, S. Dube, V. Hegde, A. Kapoor, K. Kothekar, S. Pandey, A. Rane, S. Sharma Institute for Research in Fundamental Sciences (IPM), Tehran, Iran S. Chenarani29, E. Eskandari Tadavani, S.M. Etesami29, M. Khakzad, M. Mohammadi Najafabadi, M. Naseri, S. Paktinat Mehdiabadi30, F. Rezaei Hosseinabadi, B. Safarzadeh31, M. Zeinali University College Dublin, Dublin, Ireland M. Felcini, M. Grunewald INFN Sezione di Bari a, Universitàdi Bari b, Politecnico di Bari c, Bari, Italy M. Abbresciaa,b, C. Calabriaa,b, C. Caputoa,b, A. Colaleoa, D. Creanzaa,c, L. Cristellaa,b, N. De Filippisa,c, M. De Palmaa,b, L. Fiorea, G. Iasellia,c, G. Maggia,c, M. Maggia, G. Minielloa,b, S. Mya,b, S. Nuzzoa,b, A. Pompilia,b, G. Pugliesea,c, R. Radognaa,b, A. Ranieria, G. Selvaggia,b, A. Sharmaa, L. Silvestrisa,17, R. Vendittia,b, P. Verwilligena INFN Sezione di Bologna a, Universitàdi Bologna b, Bologna, Italy G. Abbiendia, C. Battilana, D. Bonacorsia,b, S. Braibant-Giacomellia,b, L. Brigliadoria,b, R. Campaninia,b, P. Capiluppia,b, A. Castroa,b, F.R. Cavalloa, S.S. Chhibraa,b, G. Codispotia,b, M. Cuffiania,b, G.M. Dallavallea, F. Fabbria, A. Fanfania,b, D. Fasanellaa,b, P. Giacomellia, C. Grandia, L. Guiduccia,b, S. Marcellinia, G. Masettia, A. Montanaria, F.L. Navarriaa,b, A. Perrottaa, A.M. Rossia,b, T. Rovellia,b, G.P. Sirolia,b, N. Tosia,b,17 18 A The CMS Collaboration

INFN Sezione di Catania a, Universitàdi Catania b, Catania, Italy S. Albergoa,b, S. Costaa,b, A. Di Mattiaa, F. Giordanoa,b, R. Potenzaa,b, A. Tricomia,b, C. Tuvea,b INFN Sezione di Firenze a, Universitàdi Firenze b, Firenze, Italy G. Barbaglia, V. Ciullia,b, C. Civininia, R. D’Alessandroa,b, E. Focardia,b, P. Lenzia,b, M. Meschinia, S. Paolettia, L. Russoa,32, G. Sguazzonia, D. Stroma, L. Viliania,b,17 INFN Laboratori Nazionali di Frascati, Frascati, Italy L. Benussi, S. Bianco, F. Fabbri, D. Piccolo, F. Primavera17 INFN Sezione di Genova a, Universitàdi Genova b, Genova, Italy V. Calvellia,b, F. Ferroa, M.R. Mongea,b, E. Robuttia, S. Tosia,b INFN Sezione di Milano-Bicocca a, Universitàdi Milano-Bicocca b, Milano, Italy L. Brianzaa,b,17, F. Brivioa,b, V. Ciriolo, M.E. Dinardoa,b, S. Fiorendia,b,17, S. Gennaia, A. Ghezzia,b, P. Govonia,b, M. Malbertia,b, S. Malvezzia, R.A. Manzonia,b, D. Menascea, L. Moronia, M. Paganonia,b, D. Pedrinia, S. Pigazzinia,b, S. Ragazzia,b, T. Tabarelli de Fatisa,b INFN Sezione di Napoli a, Universitàdi Napoli ’Federico II’ b, Napoli, Italy, Universitàdella Basilicata c, Potenza, Italy, UniversitàG. Marconi d, Roma, Italy S. Buontempoa, N. Cavalloa,c, G. De Nardo, S. Di Guidaa,d,17, M. Espositoa,b, F. Fabozzia,c, F. Fiengaa,b, A.O.M. Iorioa,b, G. Lanzaa, L. Listaa, S. Meolaa,d,17, P. Paoluccia,17, C. Sciaccaa,b, F. Thyssena INFN Sezione di Padova a, Universitàdi Padova b, Padova, Italy, Universitàdi Trento c, Trento, Italy P. Azzia,17, N. Bacchettaa, L. Benatoa,b, D. Biselloa,b, A. Bolettia,b, R. Carlina,b, A. Carvalho Antunes De Oliveiraa,b, P. Checchiaa, M. Dall’Ossoa,b, P. De Castro Manzanoa, T. Dorigoa, U. Dossellia, F. Gasparinia,b, U. Gasparinia,b, A. Gozzelinoa, S. Lacapraraa, M. Margonia,b, A.T. Meneguzzoa,b, J. Pazzinia,b, N. Pozzobona,b, P. Ronchesea,b, F. Simonettoa,b, E. Torassaa, M. Zanettia,b, P. Zottoa,b, G. Zumerlea,b INFN Sezione di Pavia a, Universitàdi Pavia b, Pavia, Italy A. Braghieria, F. Fallavollitaa,b, A. Magnania,b, P. Montagnaa,b, S.P. Rattia,b, V. Rea, C. Riccardia,b, P. Salvinia, I. Vaia,b, P. Vituloa,b INFN Sezione di Perugia a, Universitàdi Perugia b, Perugia, Italy L. Alunni Solestizia,b, G.M. Bileia, D. Ciangottinia,b, L. Fano` a,b, P. Laricciaa,b, R. Leonardia,b, G. Mantovania,b, V. Mariania,b, M. Menichellia, A. Sahaa, A. Santocchiaa,b INFN Sezione di Pisa a, Universitàdi Pisa b, Scuola Normale Superiore di Pisa c, Pisa, Italy K. Androsova,32, P. Azzurria,17, G. Bagliesia, J. Bernardinia, T. Boccalia, R. Castaldia, M.A. Cioccia,32, R. Dell’Orsoa, S. Donatoa,c, G. Fedi, A. Giassia, M.T. Grippoa,32, F. Ligabuea,c, T. Lomtadzea, L. Martinia,b, A. Messineoa,b, F. Pallaa, A. Rizzia,b, A. Savoy-Navarroa,33, P. Spagnoloa, R. Tenchinia, G. Tonellia,b, A. Venturia, P.G. Verdinia INFN Sezione di Roma a, Universitàdi Roma b, Roma, Italy L. Baronea,b, F. Cavallaria, M. Cipriania,b, D. Del Rea,b,17, M. Diemoza, S. Gellia,b, E. Longoa,b, F. Margarolia,b, B. Marzocchia,b, P. Meridiania, G. Organtinia,b, R. Paramattia, F. Preiatoa,b, S. Rahatloua,b, C. Rovellia, F. Santanastasioa,b INFN Sezione di Torino a, Universitàdi Torino b, Torino, Italy, Universitàdel Piemonte Orientale c, Novara, Italy N. Amapanea,b, R. Arcidiaconoa,c,17, S. Argiroa,b, M. Arneodoa,c, N. Bartosika, R. Bellana,b, C. Biinoa, N. Cartigliaa, F. Cennaa,b, M. Costaa,b, R. Covarellia,b, A. Deganoa,b, N. Demariaa, 19

L. Fincoa,b, B. Kiania,b, C. Mariottia, S. Masellia, E. Migliorea,b, V. Monacoa,b, E. Monteila,b, M. Montenoa, M.M. Obertinoa,b, L. Pachera,b, N. Pastronea, M. Pelliccionia, G.L. Pinna Angionia,b, F. Raveraa,b, A. Romeroa,b, M. Ruspaa,c, R. Sacchia,b, K. Shchelinaa,b, V. Solaa, A. Solanoa,b, A. Staianoa, P. Traczyka,b INFN Sezione di Trieste a, Universit`adi Trieste b, Trieste, Italy S. Belfortea, M. Casarsaa, F. Cossuttia, G. Della Riccaa,b, A. Zanettia Kyungpook National University, Daegu, Korea D.H. Kim, G.N. Kim, M.S. Kim, S. Lee, S.W. Lee, Y.D. Oh, S. Sekmen, D.C. Son, Y.C. Yang Chonbuk National University, Jeonju, Korea A. Lee Chonnam National University, Institute for Universe and Elementary Particles, Kwangju, Korea H. Kim Hanyang University, Seoul, Korea J.A. Brochero Cifuentes, T.J. Kim Korea University, Seoul, Korea S. Cho, S. Choi, Y. Go, D. Gyun, S. Ha, B. Hong, Y. Jo, Y. Kim, K. Lee, K.S. Lee, S. Lee, J. Lim, S.K. Park, Y. Roh Seoul National University, Seoul, Korea J. Almond, J. Kim, H. Lee, S.B. Oh, B.C. Radburn-Smith, S.h. Seo, U.K. Yang, H.D. Yoo, G.B. Yu University of Seoul, Seoul, Korea M. Choi, H. Kim, J.H. Kim, J.S.H. Lee, I.C. Park, G. Ryu, M.S. Ryu Sungkyunkwan University, Suwon, Korea Y. Choi, J. Goh, C. Hwang, J. Lee, I. Yu Vilnius University, Vilnius, Lithuania V. Dudenas, A. Juodagalvis, J. Vaitkus National Centre for Particle Physics, Universiti Malaya, Kuala Lumpur, Malaysia I. Ahmed, Z.A. Ibrahim, M.A.B. Md Ali34, F. Mohamad Idris35, W.A.T. Wan Abdullah, M.N. Yusli, Z. Zolkapli Centro de Investigacion y de Estudios Avanzados del IPN, Mexico City, Mexico H. Castilla-Valdez, E. De La Cruz-Burelo, I. Heredia-De La Cruz36, A. Hernandez-Almada, R. Lopez-Fernandez, R. Magana˜ Villalba, J. Mejia Guisao, A. Sanchez-Hernandez Universidad Iberoamericana, Mexico City, Mexico S. Carrillo Moreno, C. Oropeza Barrera, F. Vazquez Valencia Benemerita Universidad Autonoma de Puebla, Puebla, Mexico S. Carpinteyro, I. Pedraza, H.A. Salazar Ibarguen, C. Uribe Estrada Universidad Aut´onomade San Luis Potos´ı, San Luis Potos´ı, Mexico A. Morelos Pineda University of Auckland, Auckland, New Zealand D. Krofcheck 20 A The CMS Collaboration

University of Canterbury, Christchurch, New Zealand P.H. Butler National Centre for Physics, Quaid-I-Azam University, Islamabad, Pakistan A. Ahmad, M. Ahmad, Q. Hassan, H.R. Hoorani, W.A. Khan, A. Saddique, M.A. Shah, M. Shoaib, M. Waqas National Centre for Nuclear Research, Swierk, Poland H. Bialkowska, M. Bluj, B. Boimska, T. Frueboes, M. Gorski,´ M. Kazana, K. Nawrocki, K. Romanowska-Rybinska, M. Szleper, P. Zalewski Institute of Experimental Physics, Faculty of Physics, University of Warsaw, Warsaw, Poland K. Bunkowski, A. Byszuk37, K. Doroba, A. Kalinowski, M. Konecki, J. Krolikowski, M. Misiura, M. Olszewski, M. Walczak Laborat´oriode Instrumenta¸c˜aoe F´ısicaExperimental de Part´ıculas,Lisboa, Portugal P. Bargassa, C. Beirao˜ Da Cruz E Silva, B. Calpas, A. Di Francesco, P. Faccioli, P.G. Ferreira Parracho, M. Gallinaro, J. Hollar, N. Leonardo, L. Lloret Iglesias, M.V. Nemallapudi, J. Rodrigues Antunes, J. Seixas, O. Toldaiev, D. Vadruccio, J. Varela Joint Institute for Nuclear Research, Dubna, Russia S. Afanasiev, P. Bunin, M. Gavrilenko, I. Golutvin, I. Gorbunov, A. Kamenev, V. Karjavin, A. Lanev, A. Malakhov, V. Matveev38,39, V. Palichik, V. Perelygin, S. Shmatov, S. Shulha, N. Skatchkov, V. Smirnov, N. Voytishin, A. Zarubin Petersburg Nuclear Physics Institute, Gatchina (St. Petersburg), Russia L. Chtchipounov, V. Golovtsov, Y. Ivanov, V. Kim40, E. Kuznetsova41, V. Murzin, V. Oreshkin, V. Sulimov, A. Vorobyev Institute for Nuclear Research, Moscow, Russia Yu. Andreev, A. Dermenev, S. Gninenko, N. Golubev, A. Karneyeu, M. Kirsanov, N. Krasnikov, A. Pashenkov, D. Tlisov, A. Toropin Institute for Theoretical and Experimental Physics, Moscow, Russia V. Epshteyn, V. Gavrilov, N. Lychkovskaya, V. Popov, I. Pozdnyakov, G. Safronov, A. Spiridonov, M. Toms, E. Vlasov, A. Zhokin Moscow Institute of Physics and Technology, Moscow, Russia T. Aushev, A. Bylinkin39 National Research Nuclear University ’Moscow Engineering Physics Institute’ (MEPhI), Moscow, Russia M. Chadeeva42, R. Chistov42, S. Polikarpov, V. Rusinov, E. Zhemchugov P.N. Lebedev Physical Institute, Moscow, Russia V. Andreev, M. Azarkin39, I. Dremin39, M. Kirakosyan, A. Leonidov39, A. Terkulov Skobeltsyn Institute of Nuclear Physics, Lomonosov Moscow State University, Moscow, Russia A. Baskakov, A. Belyaev, E. Boos, M. Dubinin43, L. Dudko, A. Ershov, A. Gribushin, V. Klyukhin, O. Kodolova, I. Lokhtin, I. Miagkov, S. Obraztsov, S. Petrushanko, V. Savrin, A. Snigirev Novosibirsk State University (NSU), Novosibirsk, Russia V. Blinov44, Y.Skovpen44, D. Shtol44 21

State Research Center of Russian Federation, Institute for High Energy Physics, Protvino, Russia I. Azhgirey, I. Bayshev, S. Bitioukov, D. Elumakhov, V. Kachanov, A. Kalinin, D. Konstantinov, V. Krychkine, V. Petrov, R. Ryutin, A. Sobol, S. Troshin, N. Tyurin, A. Uzunian, A. Volkov University of Belgrade, Faculty of Physics and Vinca Institute of Nuclear Sciences, Belgrade, Serbia P. Adzic45, P. Cirkovic, D. Devetak, M. Dordevic, J. Milosevic, V. Rekovic Centro de Investigaciones Energéticas Medioambientales y Tecnológicas (CIEMAT), Madrid, Spain J. Alcaraz Maestre, M. Barrio Luna, E. Calvo, M. Cerrada, M. Chamizo Llatas, N. Colino, B. De La Cruz, A. Delgado Peris, A. Escalante Del Valle, C. Fernandez Bedoya, J.P. Fernandez´ Ramos, J. Flix, M.C. Fouz, P. Garcia-Abia, O. Gonzalez Lopez, S. Goy Lopez, J.M. Hernandez, M.I. Josa, E. Navarro De Martino, A. Perez-Calero´ Yzquierdo, J. Puerta Pelayo, A. Quintario Olmeda, I. Redondo, L. Romero, M.S. Soares Universidad Autónomade Madrid, Madrid, Spain J.F. de Troconiz,´ M. Missiroli, D. Moran Universidad de Oviedo, Oviedo, Spain J. Cuevas, J. Fernandez Menendez, I. Gonzalez Caballero, J.R. Gonzalez´ Fernandez,´ E. Palencia Cortezon, S. Sanchez Cruz, I. Suarez´ Andres,´ P. Vischia, J.M. Vizan Garcia Instituto de F´ısicade Cantabria (IFCA), CSIC-Universidad de Cantabria, Santander, Spain I.J. Cabrillo, A. Calderon, E. Curras, M. Fernandez, J. Garcia-Ferrero, G. Gomez, A. Lopez Virto, J. Marco, C. Martinez Rivero, F. Matorras, J. Piedra Gomez, T. Rodrigo, A. Ruiz-Jimeno, L. Scodellaro, N. Trevisani, I. Vila, R. Vilar Cortabitarte CERN, European Organization for Nuclear Research, Geneva, Switzerland D. Abbaneo, E. Auffray, G. Auzinger, P. Baillon, A.H. Ball, D. Barney, P. Bloch, A. Bocci, C. Botta, T. Camporesi, R. Castello, M. Cepeda, G. Cerminara, Y. Chen, D. d’Enterria, A. Dabrowski, V. Daponte, A. David, M. De Gruttola, A. De Roeck, E. Di Marco46, M. Dobson, B. Dorney, T. du Pree, D. Duggan, M. Dunser,¨ N. Dupont, A. Elliott-Peisert, P. Everaerts, S. Fartoukh, G. Franzoni, J. Fulcher, W. Funk, D. Gigi, K. Gill, M. Girone, F. Glege, D. Gulhan, S. Gundacker, M. Guthoff, P. Harris, J. Hegeman, V. Innocente, P. Janot, J. Kieseler, H. Kirschenmann, V. Knunz,¨ A. Kornmayer17, M.J. Kortelainen, K. Kousouris, M. Krammer1, C. Lange, P. Lecoq, C. Lourenço, M.T. Lucchini, L. Malgeri, M. Mannelli, A. Martelli, F. Meijers, J.A. Merlin, S. Mersi, E. Meschi, P. Milenovic47, F. Moortgat, S. Morovic, M. Mulders, H. Neugebauer, S. Orfanelli, L. Orsini, L. Pape, E. Perez, M. Peruzzi, A. Petrilli, G. Petrucciani, A. Pfeiffer, M. Pierini, A. Racz, T. Reis, G. Rolandi48, M. Rovere, H. Sakulin, J.B. Sauvan, C. Schafer,¨ C. Schwick, M. Seidel, A. Sharma, P. Silva, P. Sphicas49, J. Steggemann, M. Stoye, Y. Takahashi, M. Tosi, D. Treille, A. Triossi, A. Tsirou, V. Veckalns50, G.I. Veres22, M. Verweij, N. Wardle, H.K. Wohri,¨ A. Zagozdzinska37, W.D. Zeuner Paul Scherrer Institut, Villigen, Switzerland W. Bertl, K. Deiters, W. Erdmann, R. Horisberger, Q. Ingram, H.C. Kaestli, D. Kotlinski, U. Langenegger, T. Rohe, S.A. Wiederkehr Institute for Particle Physics, ETH Zurich, Zurich, Switzerland F. Bachmair, L. Bani,¨ L. Bianchini, B. Casal, G. Dissertori, M. Dittmar, M. Donega,` C. Grab, C. Heidegger, D. Hits, J. Hoss, G. Kasieczka, W. Lustermann, B. Mangano, M. Marionneau, P. Martinez Ruiz del Arbol, M. Masciovecchio, M.T. Meinhard, D. Meister, F. Micheli, 22 A The CMS Collaboration

P. Musella, F. Nessi-Tedaldi, F. Pandolfi, J. Pata, F. Pauss, G. Perrin, L. Perrozzi, M. Quittnat, M. Rossini, M. Schonenberger,¨ A. Starodumov51, V.R. Tavolaro, K. Theofilatos, R. Wallny UniversitätZ ürich,Zurich, Switzerland T.K. Aarrestad, C. Amsler52, L. Caminada, M.F. Canelli, A. De Cosa, C. Galloni, A. Hinzmann, T. Hreus, B. Kilminster, J. Ngadiuba, D. Pinna, G. Rauco, P. Robmann, D. Salerno, C. Seitz, Y. Yang, A. Zucchetta National Central University, Chung-Li, Taiwan V. Candelise, T.H. Doan, Sh. Jain, R. Khurana, M. Konyushikhin, C.M. Kuo, W. Lin, A. Pozdnyakov, S.S. Yu National Taiwan University (NTU), Taipei, Taiwan Arun Kumar, P. Chang, Y.H. Chang, Y. Chao, K.F. Chen, P.H. Chen, F. Fiori, W.-S. Hou, Y. Hsiung, Y.F. Liu, R.-S. Lu, M. Minano˜ Moya, E. Paganis, A. Psallidas, J.f. Tsai Chulalongkorn University, Faculty of Science, Department of Physics, Bangkok, Thailand B. Asavapibhop, G. Singh, N. Srimanobhas, N. Suwonjandee Cukurova University - Physics Department, Science and Art Faculty A. Adiguzel, S. Cerci53, S. Damarseckin, Z.S. Demiroglu, C. Dozen, I. Dumanoglu, S. Girgis, G. Gokbulut, Y. Guler, I. Hos54, E.E. Kangal55, O. Kara, A. Kayis Topaksu, U. Kiminsu, M. Oglakci, G. Onengut56, K. Ozdemir57, D. Sunar Cerci53, B. Tali53, S. Turkcapar, I.S. Zorbakir, C. Zorbilmez Middle East Technical University, Physics Department, Ankara, Turkey B. Bilin, S. Bilmis, B. Isildak58, G. Karapinar59, M. Yalvac, M. Zeyrek Bogazici University, Istanbul, Turkey E. Gulmez,¨ M. Kaya60, O. Kaya61, E.A. Yetkin62, T. Yetkin63 Istanbul Technical University, Istanbul, Turkey A. Cakir, K. Cankocak, S. Sen64 Institute for Scintillation Materials of National Academy of Science of Ukraine, Kharkov, Ukraine B. Grynyov National Scientific Center, Kharkov Institute of Physics and Technology, Kharkov, Ukraine L. Levchuk, P. Sorokin University of Bristol, Bristol, United Kingdom R. Aggleton, F. Ball, L. Beck, J.J. Brooke, D. Burns, E. Clement, D. Cussans, H. Flacher, J. Goldstein, M. Grimes, G.P. Heath, H.F. Heath, J. Jacob, L. Kreczko, C. Lucas, D.M. Newbold65, S. Paramesvaran, A. Poll, T. Sakuma, S. Seif El Nasr-storey, D. Smith, V.J. Smith Rutherford Appleton Laboratory, Didcot, United Kingdom K.W. Bell, A. Belyaev66, C. Brew, R.M. Brown, L. Calligaris, D. Cieri, D.J.A. Cockerill, J.A. Coughlan, K. Harder, S. Harper, E. Olaiya, D. Petyt, C.H. Shepherd-Themistocleous, A. Thea, I.R. Tomalin, T. Williams Imperial College, London, United Kingdom M. Baber, R. Bainbridge, O. Buchmuller, A. Bundock, D. Burton, S. Casasso, M. Citron, D. Colling, L. Corpe, P. Dauncey, G. Davies, A. De Wit, M. Della Negra, R. Di Maria, P. Dunne, A. Elwood, D. Futyan, Y. Haddad, G. Hall, G. Iles, T. James, R. Lane, C. Laner, R. Lucas65, L. Lyons, A.-M. Magnan, S. Malik, L. Mastrolorenzo, J. Nash, A. Nikitenko51, J. Pela, B. Penning, 23

M. Pesaresi, D.M. Raymond, A. Richards, A. Rose, E. Scott, C. Seez, S. Summers, A. Tapper, K. Uchida, M. Vazquez Acosta67, T. Virdee17, J. Wright, S.C. Zenz Brunel University, Uxbridge, United Kingdom J.E. Cole, P.R. Hobson, A. Khan, P. Kyberd, I.D. Reid, P. Symonds, L. Teodorescu, M. Turner Baylor University, Waco, USA A. Borzou, K. Call, J. Dittmann, K. Hatakeyama, H. Liu, N. Pastika Catholic University of America R. Bartek, A. Dominguez The University of Alabama, Tuscaloosa, USA A. Buccilli, S.I. Cooper, C. Henderson, P. Rumerio, C. West Boston University, Boston, USA D. Arcaro, A. Avetisyan, T. Bose, D. Gastler, D. Rankin, C. Richardson, J. Rohlf, L. Sulak, D. Zou Brown University, Providence, USA G. Benelli, D. Cutts, A. Garabedian, J. Hakala, U. Heintz, J.M. Hogan, O. Jesus, K.H.M. Kwok, E. Laird, G. Landsberg, Z. Mao, M. Narain, S. Piperov, S. Sagir, E. Spencer, R. Syarif University of California, Davis, Davis, USA R. Breedon, D. Burns, M. Calderon De La Barca Sanchez, S. Chauhan, M. Chertok, J. Conway, R. Conway, P.T. Cox, R. Erbacher, C. Flores, G. Funk, M. Gardner, W. Ko, R. Lander, C. Mclean, M. Mulhearn, D. Pellett, J. Pilot, S. Shalhout, M. Shi, J. Smith, M. Squires, D. Stolp, K. Tos, M. Tripathi University of California, Los Angeles, USA M. Bachtis, C. Bravo, R. Cousins, A. Dasgupta, A. Florent, J. Hauser, M. Ignatenko, N. Mccoll, D. Saltzberg, C. Schnaible, V. Valuev, M. Weber University of California, Riverside, Riverside, USA E. Bouvier, K. Burt, R. Clare, J. Ellison, J.W. Gary, S.M.A. Ghiasi Shirazi, G. Hanson, J. Heilman, P. Jandir, E. Kennedy, F. Lacroix, O.R. Long, M. Olmedo Negrete, M.I. Paneva, A. Shrinivas, W. Si, H. Wei, S. Wimpenny, B. R. Yates University of California, San Diego, La Jolla, USA J.G. Branson, G.B. Cerati, S. Cittolin, M. Derdzinski, R. Gerosa, A. Holzner, D. Klein, V. Krutelyov, J. Letts, I. Macneill, D. Olivito, S. Padhi, M. Pieri, M. Sani, V. Sharma, S. Simon, M. Tadel, A. Vartak, S. Wasserbaech68, C. Welke, J. Wood, F. Wurthwein,¨ A. Yagil, G. Zevi Della Porta University of California, Santa Barbara - Department of Physics, Santa Barbara, USA N. Amin, R. Bhandari, J. Bradmiller-Feld, C. Campagnari, A. Dishaw, V. Dutta, M. Franco Sevilla, C. George, F. Golf, L. Gouskos, J. Gran, R. Heller, J. Incandela, S.D. Mullin, A. Ovcharova, H. Qu, J. Richman, D. Stuart, I. Suarez, J. Yoo California Institute of Technology, Pasadena, USA D. Anderson, J. Bendavid, A. Bornheim, J. Bunn, J. Duarte, J.M. Lawhorn, A. Mott, H.B. Newman, C. Pena, M. Spiropulu, J.R. Vlimant, S. Xie, R.Y. Zhu Carnegie Mellon University, Pittsburgh, USA M.B. Andrews, T. Ferguson, M. Paulini, J. Russ, M. Sun, H. Vogel, I. Vorobiev, M. Weinberg 24 A The CMS Collaboration

University of Colorado Boulder, Boulder, USA J.P. Cumalat, W.T. Ford, F. Jensen, A. Johnson, M. Krohn, S. Leontsinis, T. Mulholland, K. Stenson, S.R. Wagner Cornell University, Ithaca, USA J. Alexander, J. Chaves, J. Chu, S. Dittmer, K. Mcdermott, N. Mirman, G. Nicolas Kaufman, J.R. Patterson, A. Rinkevicius, A. Ryd, L. Skinnari, L. Soffi, S.M. Tan, Z. Tao, J. Thom, J. Tucker, P. Wittich, M. Zientek Fairfield University, Fairfield, USA D. Winn Fermi National Accelerator Laboratory, Batavia, USA S. Abdullin, M. Albrow, G. Apollinari, A. Apresyan, S. Banerjee, L.A.T. Bauerdick, A. Beretvas, J. Berryhill, P.C. Bhat, G. Bolla, K. Burkett, J.N. Butler, H.W.K. Cheung, F. Chlebana, S. Cihangir†, M. Cremonesi, V.D. Elvira, I. Fisk, J. Freeman, E. Gottschalk, L. Gray, D. Green, S. Grunendahl,¨ O. Gutsche, D. Hare, R.M. Harris, S. Hasegawa, J. Hirschauer, Z. Hu, B. Jayatilaka, S. Jindariani, M. Johnson, U. Joshi, B. Klima, B. Kreis, S. Lammel, J. Linacre, D. Lincoln, R. Lipton, M. Liu, T. Liu, R. Lopes De Sa,´ J. Lykken, K. Maeshima, N. Magini, J.M. Marraffino, S. Maruyama, D. Mason, P. McBride, P. Merkel, S. Mrenna, S. Nahn, V. O’Dell, K. Pedro, O. Prokofyev, G. Rakness, L. Ristori, E. Sexton-Kennedy, A. Soha, W.J. Spalding, L. Spiegel, S. Stoynev, J. Strait, N. Strobbe, L. Taylor, S. Tkaczyk, N.V. Tran, L. Uplegger, E.W. Vaandering, C. Vernieri, M. Verzocchi, R. Vidal, M. Wang, H.A. Weber, A. Whitbeck, Y. Wu University of Florida, Gainesville, USA D. Acosta, P. Avery, P. Bortignon, D. Bourilkov, A. Brinkerhoff, A. Carnes, M. Carver, D. Curry, S. Das, R.D. Field, I.K. Furic, J. Konigsberg, A. Korytov, J.F. Low, P. Ma, K. Matchev, H. Mei, G. Mitselmakher, D. Rank, L. Shchutska, D. Sperka, L. Thomas, J. Wang, S. Wang, J. Yelton Florida International University, Miami, USA S. Linn, P. Markowitz, G. Martinez, J.L. Rodriguez Florida State University, Tallahassee, USA A. Ackert, T. Adams, A. Askew, S. Bein, S. Hagopian, V. Hagopian, K.F. Johnson, T. Kolberg, H. Prosper, A. Santra, R. Yohay Florida Institute of Technology, Melbourne, USA M.M. Baarmand, V. Bhopatkar, S. Colafranceschi, M. Hohlmann, D. Noonan, T. Roy, F. Yumiceva University of Illinois at Chicago (UIC), Chicago, USA M.R. Adams, L. Apanasevich, D. Berry, R.R. Betts, I. Bucinskaite, R. Cavanaugh, O. Evdokimov, L. Gauthier, C.E. Gerber, D.J. Hofman, K. Jung, I.D. Sandoval Gonzalez, N. Varelas, H. Wang, Z. Wu, M. Zakaria, J. Zhang The University of Iowa, Iowa City, USA B. Bilki69, W. Clarida, K. Dilsiz, S. Durgut, R.P. Gandrajula, M. Haytmyradov, V. Khristenko, J.-P. Merlo, H. Mermerkaya70, A. Mestvirishvili, A. Moeller, J. Nachtman, H. Ogul, Y. Onel, F. Ozok71, A. Penzo, C. Snyder, E. Tiras, J. Wetzel, K. Yi Johns Hopkins University, Baltimore, USA B. Blumenfeld, A. Cocoros, N. Eminizer, D. Fehling, L. Feng, A.V. Gritsan, P. Maksimovic, J. Roskes, U. Sarica, M. Swartz, M. Xiao, C. You 25

The University of Kansas, Lawrence, USA A. Al-bataineh, P. Baringer, A. Bean, S. Boren, J. Bowen, J. Castle, L. Forthomme, R.P. Kenny III, S. Khalil, A. Kropivnitskaya, D. Majumder, W. Mcbrayer, M. Murray, S. Sanders, R. Stringer, J.D. Tapia Takaki, Q. Wang Kansas State University, Manhattan, USA A. Ivanov, K. Kaadze, Y. Maravin, A. Mohammadi, L.K. Saini, N. Skhirtladze, S. Toda Lawrence Livermore National Laboratory, Livermore, USA F. Rebassoo, D. Wright University of Maryland, College Park, USA C. Anelli, A. Baden, O. Baron, A. Belloni, B. Calvert, S.C. Eno, C. Ferraioli, J.A. Gomez, N.J. Hadley, S. Jabeen, G.Y. Jeng, R.G. Kellogg, J. Kunkle, A.C. Mignerey, F. Ricci-Tam, Y.H. Shin, A. Skuja, M.B. Tonjes, S.C. Tonwar Massachusetts Institute of Technology, Cambridge, USA D. Abercrombie, B. Allen, A. Apyan, V. Azzolini, R. Barbieri, A. Baty, R. Bi, K. Bierwagen, S. Brandt, W. Busza, I.A. Cali, M. D’Alfonso, Z. Demiragli, G. Gomez Ceballos, M. Goncharov, D. Hsu, Y. Iiyama, G.M. Innocenti, M. Klute, D. Kovalskyi, K. Krajczar, Y.S. Lai, Y.-J. Lee, A. Levin, P.D. Luckey, B. Maier, A.C. Marini, C. Mcginn, C. Mironov, S. Narayanan, X. Niu, C. Paus, C. Roland, G. Roland, J. Salfeld-Nebgen, G.S.F. Stephans, K. Tatar, D. Velicanu, J. Wang, T.W. Wang, B. Wyslouch University of Minnesota, Minneapolis, USA A.C. Benvenuti, R.M. Chatterjee, A. Evans, P. Hansen, S. Kalafut, S.C. Kao, Y. Kubota, Z. Lesko, J. Mans, S. Nourbakhsh, N. Ruckstuhl, R. Rusack, N. Tambe, J. Turkewitz University of Mississippi, Oxford, USA J.G. Acosta, S. Oliveros University of Nebraska-Lincoln, Lincoln, USA E. Avdeeva, K. Bloom, D.R. Claes, C. Fangmeier, R. Gonzalez Suarez, R. Kamalieddin, I. Kravchenko, A. Malta Rodrigues, J. Monroy, J.E. Siado, G.R. Snow, B. Stieger State University of New York at Buffalo, Buffalo, USA M. Alyari, J. Dolen, A. Godshalk, C. Harrington, I. Iashvili, J. Kaisen, D. Nguyen, A. Parker, S. Rappoccio, B. Roozbahani Northeastern University, Boston, USA G. Alverson, E. Barberis, A. Hortiangtham, A. Massironi, D.M. Morse, D. Nash, T. Orimoto, R. Teixeira De Lima, D. Trocino, R.-J. Wang, D. Wood Northwestern University, Evanston, USA S. Bhattacharya, O. Charaf, K.A. Hahn, A. Kumar, N. Mucia, N. Odell, B. Pollack, M.H. Schmitt, K. Sung, M. Trovato, M. Velasco University of Notre Dame, Notre Dame, USA N. Dev, M. Hildreth, K. Hurtado Anampa, C. Jessop, D.J. Karmgard, N. Kellams, K. Lannon, N. Marinelli, F. Meng, C. Mueller, Y. Musienko38, M. Planer, A. Reinsvold, R. Ruchti, N. Rupprecht, G. Smith, S. Taroni, M. Wayne, M. Wolf, A. Woodard The Ohio State University, Columbus, USA J. Alimena, L. Antonelli, B. Bylsma, L.S. Durkin, S. Flowers, B. Francis, A. Hart, C. Hill, R. Hughes, W. Ji, B. Liu, W. Luo, D. Puigh, B.L. Winer, H.W. Wulsin 26 A The CMS Collaboration

Princeton University, Princeton, USA S. Cooperstein, O. Driga, P. Elmer, J. Hardenbrook, P. Hebda, D. Lange, J. Luo, D. Marlow, T. Medvedeva, K. Mei, I. Ojalvo, J. Olsen, C. Palmer, P. Piroue,´ D. Stickland, A. Svyatkovskiy, C. Tully University of Puerto Rico, Mayaguez, USA S. Malik Purdue University, West Lafayette, USA A. Barker, V.E. Barnes, S. Folgueras, L. Gutay, M.K. Jha, M. Jones, A.W. Jung, A. Khatiwada, D.H. Miller, N. Neumeister, J.F. Schulte, X. Shi, J. Sun, F. Wang, W. Xie Purdue University Calumet, Hammond, USA N. Parashar, J. Stupak Rice University, Houston, USA A. Adair, B. Akgun, Z. Chen, K.M. Ecklund, F.J.M. Geurts, M. Guilbaud, W. Li, B. Michlin, M. Northup, B.P. Padley, J. Roberts, J. Rorie, Z. Tu, J. Zabel University of Rochester, Rochester, USA B. Betchart, A. Bodek, P. de Barbaro, R. Demina, Y.t. Duh, T. Ferbel, M. Galanti, A. Garcia- Bellido, J. Han, O. Hindrichs, A. Khukhunaishvili, K.H. Lo, P. Tan, M. Verzetti Rutgers, The State University of New Jersey, Piscataway, USA A. Agapitos, J.P. Chou, Y. Gershtein, T.A. Gomez´ Espinosa, E. Halkiadakis, M. Heindl, E. Hughes, S. Kaplan, R. Kunnawalkam Elayavalli, S. Kyriacou, A. Lath, K. Nash, M. Osherson, H. Saka, S. Salur, S. Schnetzer, D. Shefﬁeld, S. Somalwar, R. Stone, S. Thomas, P. Thomassen, M. Walker University of Tennessee, Knoxville, USA A.G. Delannoy, M. Foerster, J. Heideman, G. Riley, K. Rose, S. Spanier, K. Thapa Texas A&M University, College Station, USA O. Bouhali72, A. Celik, M. Dalchenko, M. De Mattia, A. Delgado, S. Dildick, R. Eusebi, J. Gilmore, T. Huang, E. Juska, T. Kamon73, R. Mueller, Y. Pakhotin, R. Patel, A. Perloff, L. Pernie,` D. Rathjens, A. Safonov, A. Tatarinov, K.A. Ulmer Texas Tech University, Lubbock, USA N. Akchurin, J. Damgov, F. De Guio, C. Dragoiu, P.R. Dudero, J. Faulkner, E. Gurpinar, S. Kunori, K. Lamichhane, S.W. Lee, T. Libeiro, T. Peltola, S. Undleeb, I. Volobouev, Z. Wang Vanderbilt University, Nashville, USA S. Greene, A. Gurrola, R. Janjam, W. Johns, C. Maguire, A. Melo, H. Ni, P. Sheldon, S. Tuo, J. Velkovska, Q. Xu University of Virginia, Charlottesville, USA M.W. Arenton, P. Barria, B. Cox, J. Goodell, R. Hirosky, A. Ledovskoy, H. Li, C. Neu, T. Sinthuprasith, X. Sun, Y. Wang, E. Wolfe, F. Xia Wayne State University, Detroit, USA C. Clarke, R. Harr, P.E. Karchin, J. Sturdy University of Wisconsin - Madison, Madison, WI, USA D.A. Belknap, J. Buchanan, C. Caillol, S. Dasu, L. Dodd, S. Duric, B. Gomber, M. Grothe, M. Herndon, A. Herve,´ P. Klabbers, A. Lanaro, A. Levine, K. Long, R. Loveless, T. Perry, G.A. Pierro, G. Polese, T. Ruggles, A. Savin, N. Smith, W.H. Smith, D. Taylor, N. Woods 27

†: Deceased 1: Also at Vienna University of Technology, Vienna, Austria 2: Also at State Key Laboratory of Nuclear Physics and Technology, Peking University, Beijing, China 3: Also at Institut Pluridisciplinaire Hubert Curien (IPHC), Universite´ de Strasbourg, CNRS/IN2P3, Strasbourg, France 4: Also at Universidade Estadual de Campinas, Campinas, Brazil 5: Also at Universidade Federal de Pelotas, Pelotas, Brazil 6: Also at Universite´ Libre de Bruxelles, Bruxelles, Belgium 7: Also at Deutsches Elektronen-Synchrotron, Hamburg, Germany 8: Also at Joint Institute for Nuclear Research, Dubna, Russia 9: Also at Helwan University, Cairo, Egypt 10: Now at Zewail City of Science and Technology, Zewail, Egypt 11: Now at Fayoum University, El-Fayoum, Egypt 12: Also at British University in Egypt, Cairo, Egypt 13: Now at Ain Shams University, Cairo, Egypt 14: Also at Universite´ de Haute Alsace, Mulhouse, France 15: Also at Skobeltsyn Institute of Nuclear Physics, Lomonosov Moscow State University, Moscow, Russia 16: Also at Tbilisi State University, Tbilisi, Georgia 17: Also at CERN, European Organization for Nuclear Research, Geneva, Switzerland 18: Also at RWTH Aachen University, III. Physikalisches Institut A, Aachen, Germany 19: Also at University of Hamburg, Hamburg, Germany 20: Also at Brandenburg University of Technology, Cottbus, Germany 21: Also at Institute of Nuclear Research ATOMKI, Debrecen, Hungary 22: Also at MTA-ELTE Lendulet¨ CMS Particle and Nuclear Physics Group, Eotv¨ os¨ Lorand´ University, Budapest, Hungary 23: Also at Institute of Physics, University of Debrecen, Debrecen, Hungary 24: Also at Indian Institute of Technology Bhubaneswar, Bhubaneswar, India 25: Also at University of Visva-Bharati, Santiniketan, India 26: Also at Indian Institute of Science Education and Research, Bhopal, India 27: Also at Institute of Physics, Bhubaneswar, India 28: Also at University of Ruhuna, Matara, Sri Lanka 29: Also at Isfahan University of Technology, Isfahan, Iran 30: Also at Yazd University, Yazd, Iran 31: Also at Plasma Physics Research Center, Science and Research Branch, Islamic Azad University, Tehran, Iran 32: Also at Universita` degli Studi di Siena, Siena, Italy 33: Also at Purdue University, West Lafayette, USA 34: Also at International Islamic University of Malaysia, Kuala Lumpur, Malaysia 35: Also at Malaysian Nuclear Agency, MOSTI, Kajang, Malaysia 36: Also at Consejo Nacional de Ciencia y Tecnolog´ıa, Mexico city, Mexico 37: Also at Warsaw University of Technology, Institute of Electronic Systems, Warsaw, Poland 38: Also at Institute for Nuclear Research, Moscow, Russia 39: Now at National Research Nuclear University ’Moscow Engineering Physics Institute’ (MEPhI), Moscow, Russia 40: Also at St. Petersburg State Polytechnical University, St. Petersburg, Russia 41: Also at University of Florida, Gainesville, USA 42: Also at P.N. Lebedev Physical Institute, Moscow, Russia 28 A The CMS Collaboration

43: Also at California Institute of Technology, Pasadena, USA 44: Also at Budker Institute of Nuclear Physics, Novosibirsk, Russia 45: Also at Faculty of Physics, University of Belgrade, Belgrade, Serbia 46: Also at INFN Sezione di Roma; Universita` di Roma, Roma, Italy 47: Also at University of Belgrade, Faculty of Physics and Vinca Institute of Nuclear Sciences, Belgrade, Serbia 48: Also at Scuola Normale e Sezione dell’INFN, Pisa, Italy 49: Also at National and Kapodistrian University of Athens, Athens, Greece 50: Also at Riga Technical University, Riga, Latvia 51: Also at Institute for Theoretical and Experimental Physics, Moscow, Russia 52: Also at Albert Einstein Center for Fundamental Physics, Bern, Switzerland 53: Also at Adiyaman University, Adiyaman, Turkey 54: Also at Istanbul Aydin University, Istanbul, Turkey 55: Also at Mersin University, Mersin, Turkey 56: Also at Cag University, Mersin, Turkey 57: Also at Piri Reis University, Istanbul, Turkey 58: Also at Ozyegin University, Istanbul, Turkey 59: Also at Izmir Institute of Technology, Izmir, Turkey 60: Also at Marmara University, Istanbul, Turkey 61: Also at Kafkas University, Kars, Turkey 62: Also at Istanbul Bilgi University, Istanbul, Turkey 63: Also at Yildiz Technical University, Istanbul, Turkey 64: Also at Hacettepe University, Ankara, Turkey 65: Also at Rutherford Appleton Laboratory, Didcot, United Kingdom 66: Also at School of Physics and Astronomy, University of Southampton, Southampton, United Kingdom 67: Also at Instituto de Astrof´ısica de Canarias, La Laguna, Spain 68: Also at Utah Valley University, Orem, USA 69: Also at Argonne National Laboratory, Argonne, USA 70: Also at Erzincan University, Erzincan, Turkey 71: Also at Mimar Sinan University, Istanbul, Istanbul, Turkey 72: Also at Texas A&M University at Qatar, Doha, Qatar 73: Also at Kyungpook National University, Daegu, Korea